Coverage Enhancement Algorithm for WSNs Based on Vampire Bat and Improved Virtual Force

Coverage enhancement is an important strategy to avoid coverage holes caused by the random deployment of sensor nodes. Given the harsh physical environments of wireless sensor networks (WSNs), which impede the energy supplement and recovery of sensor nodes, the motivation of our research is to repair the coverage holes and reduce the energy consumption during the deployment of sensor nodes. Firstly, by using cellular grids to stack the monitoring area, a bipartite graph model between the nodes and the cellular grids is constructed to minimize and balance the moving distance during the redeployment. Secondly, the vampire bat algorithm is introduced for bipartite graph matching. Finally, the coverage effect and moving distance are further optimized based on the improved virtual force. The simulation results show that the coverage rate is increased by 5.43%, 3.25%, and 1.63%, and the moving distance is reduced by 33.64%, 3.66%, and 2.01% when compared with COSH, VF-IALO, and HA, respectively. In addition, the proposed algorithm shows good performance in terms of uniformity of moving distance and maximum moving distance.